Several years ago, lumber treated with chromated copper arsenate (known as CCA) was considered the answer to applications where wood is exposed to the elements. With longer life than rot-resistant species like redwood, you could purchase it almost anywhere, and manufacturers said the treatment chemicals, though toxic, safely stayed put in the wood. The main plus for DIY'ers is the chemicals didn't harm plants, unlike creosote and pentachloro-phenol, two previously popular wood preservatives.
Without a non-toxic fence post treatment, people were forced to use pressure treated lumber for applications where the lumber is direct buried or exposed to the elements. By applying Rubberizeit!™ Liquid Rubber Coating Solutions (which are paintable) on non-treated lumber, you create a watertight seal which is also suitable for direct buried applications. Therefore, eliminating the need for pressure treated lumber.
What are you gaining by using a non-toxic fence post treatment?
In the pressure-treating process, lumber is sealed in a tank, and air is extracted, which creates a vacuum. Then a solution containing chromium, copper, and arsenic is added. Because of the vacuum, the chemicals are carried deep into the wood. All three chemicals are toxic, however, chromium and copper don't raise many concerns. It's arsenic that is worrisome.
In the below video we used our non-toxic fence post treatment and apply it to untreated lumber to create a fence. We sealed the posts with Rubberizeit!™ Liquid Rubber Coating Solutions and also coated the area of the post and rung where the two meet (to create a gasket). We then coated the tops of the posts as well as the tops of the rungs to prevent water ingress through the top surface. After all the Liquid Rubber had cured, we painted the fence with a charcoal exterior grade latex based fence & deck stain. You can also coat treated post as well to prevent then form leaching.